Steel link chain

ABSTRACT

1,099,213. Chains; circlips. REIMERS GETRIEBE A.G. Nov. 24, 1965 [Nov. 25, 1964], No. 49928/65. Headings F2H and F2Q. In a link chain for a conical pulley gear, link pins 2, 2&lt;SP&gt;1&lt;/SP&gt; are locked axially by a member 7 which engages grooves 3, Fig. 3, located at the centre of triangular longitudinal projections 4 on the pins 2, 2&lt;SP&gt;1&lt;/SP&gt;. The projections 4 are located in recesses 5 in the walls of the bores in which the pins are located. The member 7 may be secured in a locking position by bending a lug 9 over one of the chain links. In a modification, a locking groove 13 is provided in the edge of a pin, Fig. 6. In a further modification a locking element 22, Fig. 7, is provided with detents 23, 23&lt;SP&gt;1&lt;/SP&gt; which are adapted to engage locking grooves in one of each pair of adjacent link pins. The other link pins of the pairs are locked by a similar element 22.

Nov. 21, 1967 w. KETTERLE ET AL 3,353,421

I STEEL LINK CHAIN 2 Sheets-Sheet 1 Filed Nov. 26, 1965 Fig.12

Fig.10 Fig.11'1

INVENTORS' Nov. 21,1967 w, -r ET AL 3,353,421

STEEL LINK CHAIN 2 Sheets-Sheet 2 Filed Nov. 26, 1965 FA 21. 24 27 24 24' ea- Fig.18

' .26 31 31' Fig.20

nrnlemzys United States Patent 3,353,421 STEEL LINK CHAIN Walter Ketterle, Oberursel, and Herbert Steuer and Raimund Pataky, Bad Homburg vor der Hoke, Germany, assignors to Reimers Getriebe Kommanditgesellschaft, Ascona, Switzerland Filed Nov. 26, 1965, Ser. No. 509,920 Claims priority, application Germany, Nov. 25, 1964, R 39,312 12 Claims. (Cl. 74-453) The present invention relates to a link chain which preferably consists of steel and comprises a plurality of chain links which are pivotably connected to each other by link pins and in which each chain link may either consist of a one-piece element or of a set of individual parallel side bars, while each link pin preferably consists of a pair of rocking members which are adapted to rock on each other when during the operation of the chain the adjacent chain links are pivoted relative to each other. More particularly, the invention relates to a link chain of the above-mentioned type which is especially adapted for being employed in an infinitely variable cone pulley transmission in which this chain transmits the power from one pair of pulley disks to the other.

When such a chain is under tension and the link pins extend exactly at right angles to the direction of travel of the chain, and also when during the operation of the chain the link pins always remain in a horizontal position, there should at least theoretically be no danger that these pins might slide longitudinally within the bores of the chain links, that is, transverse to the direction of travel of the chain. However, even under such conditions it is advisable to lock the link pins in some manner relative to the chain links since there is always the possibility that additional forces may occur, for example, as the result of vibrations, which may cause the link pins to slide laterally out of the chain links. It is also advisable to secure the link pins within the chain links in order to facilitate the assembly and installation of the chain and also for preventing the chain from falling apart during shipment, and such securing means are, of course, absolutely required especially during the operation of the chain if the link pins do not at all times remain in a horizontal position.

The most simple manner of locking the link ins in a fixed position relative to the chain links consists in upsetting or riveting their ends, provided these pins are of the solid cylindrical type. Underneath these riveted ends, they are preferably provided with washers. Although the link pins do not have to be quite as long if such washers are omitted, such omission may impair the flexibility of the chain. Another possibility of securing the link pins within the chain links consists in providing their outer ends with transverse bores and of inserting a cotter pin into each bore. The link pins may also in this case be provided with washers underneath the cotter pins or such washers may be omitted. This manner of securing the link pins avoids the danger that they may be deformed by an upsetting or riveting operation and that as the result of such a deformation they might fit improperly or too tightly into the chain links. On the other hand, when using cotter pins, the ends of the link pins are weakened by the transverse bores, and therefore the solidity of the chain and its resistance to pressure in the direction transverse to its direction of travel is considerably reduced. Furthermore, when such a chain which is provided with cotter pins is used in a cone pulley transmission, there is always the danger that these cotter pins may interfere with the proper entry of the chain between each pair of conical friction disks.

3,353,421 Patented Nov. 21, 1967 A further possibility of securing solid link pins to the chain links consists of providing one or both outer ends of each pin with a peripheral groove, and of inserting a snap ring into this groove. This type of construction has the advantage that the axial position of the link pins within the chain links may be fixed quite accurately and that because of the large surface contact of the snap rings with the chain links, the wear upon these rings will be quite small. However, in all other respects this mannerof securing the link pins has the same disadvantages as that of providing the link pins with transverse bores for the insertion of cotter pins, namely, that the cross-sectional area of the pins is reduced by the peripheral grooves and that the pins are therefore weakened, and further that these pins must project laterally from the chain and therefore render it difficult to exert a lateral pressure upon the chain, for example, in a cone pulley transmission.

All of the means as previously mentioned for securing solid one-piece link pins to chain links also have the disadvantage that they increase the cost of manufacture of the chain very considerably and also render its assembly very difficult.

If the link pins are divided and each of them forms a pair of parallel rocking members with curved longitudinal surfaces engaging upon and adapted to rock or roll on each other, most of the known locking means for one-piece link pins cannot be employed for preventing these rocking members from sliding in their longitudinal direction within the links. Since such rocking members eliminate or at least considerably reduce the friction in the joints of the chain links and thus the wear thereon, the chains of this type are very preferred for high-duty purposes. Therefore it became imperative also to devise suitable means which will prevent the rocking members of such chains from sliding longitudinally within the chain links, that is, transverse to the direction of travel of the chain. In one known chain structure this is accomplished by providing the outer ends of each pair of rocking members with transverse grooves into which a snap ring is inserted so as to encompass both rocking members. This has the disadvantage that it is very difiicult and expensive to provide the individual noncylindrical rocking members with corresponding transverse grooves. Furthermore, since the cross-sectional area of the rocking members should be reduced and weakened as little as possible, the groove in each pair of these members should be as shallow and narrow as possible which, in turn, means that the snap ring must be very thin. However, since the two rocking members of the same pair rock on each other when the adjacent chain links are pivoted relative to each other, a considerable friction may occur between the snap ring and the rocking members which has the result that the movability of :the rocking members and also of the chain will be reduced and the snap ring will be worn until eventually it may break.

It is an object of the present invention to provide an improved link chain, the individual links of which may either consist of one-piece elements or may be assembled of a plurality of parallel side bars, and in which each link pin which pivotably connects the adjacent chain links to each other is preferably divide-d so as to form a pair of rocking members as previously described. A further object of the invention consists in providing these link pins or rocking members with suitable locking means which do not possess the above-mentioned disadvantages of the locking means as previously employed. This is attained according to the invention by providing each link pin or rocking member with one or more locking recesses which extend transversely to its longitudinal direction and are provided only within a small part of its peripheral surface, and by further providing a suitable locking element which engages into this recess and prevents the link pin or at least one of the two rocking members which are adapted to rock on each other from sliding longitudinally within the bore of the adjacent chain links, that is, transversely to the direction of travel of the chain.

According to the invention, these locking recesses may be of different designs and may consist, for example, of straight grooves which may be formed by milling or punching operations and which are adapted to receive a clamplike locking element which may consist, for example, of sheet metal. These transverse grooves may be provided either in parts of the rocking members which, when the latter are inserted into the chain links, are located either at .the inside or atthe outside of the chain. If the locking elements are inserted into these locking grooves of the rocking members at the inside of the chain, that is, between the side bars of the adjacent links, the rocking members may have a length equal to the width of the chain links and will not project therefrom. Only a single locking element is then required for preventing a one-piece link pin or both rocking members of one pair from sliding in their longitudinal directions. If the link pins consist of rocking members, the transverse groove is preferably provided in at least one longitudinal edge of each rocking member, while in rocking members which are provided with a central longitudinal projection opposite to their rocking surfaces, the locking groove is provided in this projection. In the last-mentioned case, the locking element may consist of a circular disk, the bore of Which has an inner diameter slightly larger than the diameter of the bore in the chain links and has a recess in its wall into which the longitudinal projection on one rocking member may be inserted. This locking disk is further provided with an outwardly projecting lug. After the chain has been assembled and the locking disk has been inserted into the locking grooves of the rocking member and after the rocking member has then been turned about its axis to a position in which the lug projects from the chain links, this lug may be bent over the adjacent chain link so as to lock it thereto.

This locking element is preferably inserted between the side bars of two adjacent chain links so that only one locking element Will be required for securing each pair of rocking members. If the locking element is open on one side and therefore consists of two arms which are adapted to embrace a pair of rocking members, it may be slipped between the adjacent chain links and over the rocking members after the latter have been inserted into the chain links.

According to another embodiment of the invention, the locking element for such rocking members may consist of aslotted locking ring of spring steel which engages into the mentioned locking grooves in the rocking members. In its contracted position, this locking ring has an inner diameter slightly larger than the outer diameter of each pair of rocking members. Thus, there is a small amount of play between each pair of rocking members and the locking ring which permits the rocking members to rock freely and without undue friction on each other without being restrained by the locking ring. When sufficiently resilient, the locking ring may also engage tightly around the rocking members. This resilience may be attained, for example, by bending the back of the locking ring opposite to the slot between its ends so as to form a U- shaped projection. Instead of employing such a resilient ring, it is also possible to prevent any binding action on the rocking members by providing the locking element in the form of a U-shaped wire of a soft material which, after the chain has been assembled, is slipped over the rocking members and into the mentioned locking grooves therein and the free ends of which are then bent toward each other over the rocking members.

If the transverse locking groove or grooves are provided in one or both longitudinal edges of each rocking member, which has the advantage that these grooves may be produced in the same stamping operation in which the end surfaces of the rocking member are formed, the circular locking element according to the invention is provided with a locking surface which projects into the bore of this element into which the pair of rocking members are inserted during the assembly of the chain. When this locking element is then turned about the rocking members, the inwardly projecting part thereof will engage into the locking groove in the longitudinal edges of the rocking members. If the locking element consists of a resilient ring which may be snapped over the pair of rocking members, the back of this ring opposite to the slot between its ends may be bent toward the inside of the ring. When this locking ring has been slipped over the pair of rocking members, the inwardly bent portion of this ring will engage into the locking grooves in one longitudinal edge of the two rocking members and thereby prevents them from sliding in their longitudinal direction.

If each individual chain link consists of a set of parallel side bars which are clamped together, for example, by a U-shaped bracket, the locking element preferably consists of a strip of sheet metal of a shape similar to one of the side bars. The wall of each of the two bores of this locking strip is then provided with an inwardly projecting detent which is adapted to engage only into one of the two rocking members which are directly associated with this particular chain link. The bores of this lock-- ing strip are enlarged or elongated at the side opposite to the detent at least to an extent equal to the maximum height of the detent from the wall of the bore. Furthermore, one of the longitudinal sides of the locking strip is provided with an outwardly projecting lug. This locking strip is to be inserted between two adjacent side bars of one chain link and held therein in such a position that when the rocking members are being inserted into the bores of the link, they will pass above the detents through the bores in the locking strip. After the rocking members have been fully inserted into the chain link, the locking strip is shifted transversely to the direction of travel of the chain so that the detents will then engage into the locking grooves of the rocking members which are directly associated with this chain link. One of the rocking members of each pair is therefore locked by a locking strip which is inserted into this chain link, while the other rocking member of each pair is locked by a similar locking strip which is inserted into one of the adjacent chain links. After each locking strip has been shifted so that its detents engage into the locking grooves of the respective rocking members, the projecting lug of this strip is bent over the adjacent side bar so as to maintain this strip in its locking position.

Another very advantageous modifications of the invention in which the chain links likewise consist of individual parallel side bars of sheet steel provides that one of the side bars of each link forms a locking element in which the wall of each circular bore is provided with an inwardly projecting detent which is adapted to be inserted into the transverse locking groove in one of the rocking members. A chain of this design does not require any additional locking elements and is therefore of a lighter weight and may be more easily assembled. During the assembly of the chain, the first of the rocking members of one pair is inserted into one of the bores of the chain link and locked therein. The second rocking member of this pair may then also be inserted after the side bar carrying the locking detent has been pivoted so that this detent does not interfere with the insertion. After this side bar has been pivoted back to its normal position, both rocking members are locked against sliding in their longitudinal direction.

The numerous features and advantages of the present invention will become more clearly apparent from the following detailed description thereof which is to be read with reference to the accompanying drawings, in which it is assumed that the chain according to the invention is employed as a driving element for connecting the two pairs of conical disks of a cone pulley transmission, and in which FIGURE 1 shows a central longitudinal section of the joint between two adjacent chain links and illustrates the rocking members connecting the links and a circular diskshaped locking element mounted on these rocking members;

FIGURE 2 shows a plan view of the locking element according to FIGURE 1;

FIGURE 3 shows a perspective view of one of the rocking members according to FIGURE 1;

FIGURE 4 shows a central longitudinal section of a joint similar to that as shown in FIGURE 1, but provided with modified rocking members and a modified locking element;

FIGURE 5 shows a plan view of the locking element according to FIGURE 4;

FIGURE 6 shows a perspective view of one of the rocking members according to FIGURE 4;

FIGURE 7 shows another view similar to FIGURE 1, but with rocking members and a locking element according to another modification of the invention;

FIGURE 8 shows a similar view of a joint, in which the locking element consists of a resilient ring;

FIGURE 9 shows a perspective view of a rocking member as employed in the joints according to FIGURES 8, 10, and 11;

FIGURE 10 shows a view similar to FIGURE 8 of a joint which is provided with a locking element in the form of a ring of soft wire;

FIGURE 11 shows a view similar to FIGURE 8 of a joint with a locking element in the form of a resilient ring of a different shape;

FIGURE 12 shows another view similar to FIGURE 8 but with a pair of rocking members of a slightly different construction which are locked by a resilient ring of a different shape;

FIGURE 13 shows a plan view of a locking plate which is designed for locking one rocking member of each of two pairs which connect one chain link with the ad acent links;

FIGURE 14 shows :a central longitudinal section of the joints between three adjacent chain links into which the locking plates according to FIGURE 13 are inserted;

FIGURE 15 shows a perspective view of one of the rocking members according to FIGURE 14;

FIGURE 16 shows a top view, partly broken away, of the chain links according to FIGURE 14;

FIGURE 17 shows a plan view of a locking element in the form of a side bar;

FIGURE 18 shows a central longitudinal section of the joints between three adjacent chain links in whlch the rocking members are locked by locking elements according to FIGURE 17;

FIGURE 19 shows a perspective v1ew of one rocking members according to FIGURE 18; while FIGURE 20 shows a cross section which is taken along the line AA of FIGURE 18.

As illustrated in FIGURES 1 to .3 of the drawings, each link pin for pivotably connecting two adjacent chain links 1 and 1 to each other consists of a pair of rocking members 2 and 2' which are inserted into the coinciding bores of the links and extend parallel to each other transversely to the direction of travel of the chain. Both rocking members 2 and 2' are provided on their inner sides facing each other with arcuate rocking surfaces 6 and 6 which are adapted to rock or roll along each other when the two chain links 1 and 1' are pivoted relative to each other. The outer sides of both rocking members 2 and 2 opposite to the rocking surfaces 6 and 6 are likewise of generally arcuate shape and have a radius of curvature equal to that of the walls of the bores in the chain links 1 and 1'. However, centrally of this outer side each rocking member 2 and 2' is provided with a longitudinal of the projection 4 of a triangular cross section which is interrupted at the center of its length by a locking groove 3. When the rocking members 2 and 2' are inserted into the coinciding bores of two adjacent chain links 1 and 1' these longitudinal projections 4 engage into recesses 5 in the walls of these bores and secure the rocking members from turning within these bores. When the chain is being assembled, a locking disk 7 which is provided with a recess 8 in the wall of its central bore is inserted between two adjacent links at the center of their width to the position as indicated in FIGURE 1 in dot-and-dash lines, in which the recess 8 is in alignment with the recesses 5, for example, in the left side of the walls of the bores of the chain links. Thereupon the rocking member 2 is inserted into the bores of the chain links and into the bore of locking disk 7 and held therein in a position in which the projection 4 of this locking member 2 is located direcly in front of the recesses 5 in the right side of the bore walls of the chain links and in which the locking groove 3 in the projection 4 faces the inner wall of the locking disk 7. Rocking member 2 is then moved toward the right and presses against the bore walls of the chain links so that the projection 4 engages into the recesses 5 and the wall of the bore of disk '7 enters into the locking groove 3 in the projection 4 of rocking member 2 and thereby prevents the latter from sliding in its longitudinal direction. Thereafter the left rocking member 2 is inserted into the left part of the bores in the chain links by sliding its curved outer surface 6' along the walls of these bores, while its projection 4 engages into the left recess 5 in the chain links, until the locking groove 3 of this projection 4 coincides with the recess 8 in disk 7. When both rocking members 2 and 2 are thus properly inserted, the locking disk 7 is turned toward the right to the position as shown in full lines in FIGURE 1, whereby the inner wall of disk 7 also enters into the locking groove 3 of the rocking member 2' and thereby also looks the latter within the chain links. An outwardly projecing lug on locking disk 7 is then bent over one of the chain links so as to secure the locking disk 7 in its locking position in which both rocking members 2 and 2' are prevented from sliding in the transverse direction of the chain.

FIGURE 7 illustrates a similar locking element 10 which, however, may be more easily installed and is for this purpose not made of a circular shape but of a bifurcated shape which permits both rocking members 2 and 2' first to be inserted into the bores in the chain links 1 and 1 before the locking element 10 is inserted from the outer side of the chain. The two resilient arms of this locking element are then fitted into the locking grooves 3 in the projections 4 of rocking members 2 and 2' and are thereafter snapped over the latter. This locking element 10 is likewise provided with a projecting lug 9 which is then bent over the adjacent chain link so as to secure the locking element 10 in its locking position.

FIGURES 4 to 6 illustrate a modification of the invention in which one of the longitudinal edges of each rocking member 2 and 2' is provided with a locking groove 13 which may be cut in the same operation in which the two end surfaces 11 and 11 of each rocking member are produced. If the chain is intended for use in a cone pulley transmission in which the power is transmitted by lateral pressure between a pair of conical friction disks and the opposite sides of the chain, these end surfaces 11 and 11 are inclined in accordance with the angle of the conical disks of the transmission. In addition, these end surfaces may be cambered. In order to prevent the two rocking members 2 and 2' from sliding transversely of the chain links 1 and 1', a locking disk 17 is provided which has a locking portion 12 projecting into the bore of the disk and a pair of opposite recesses 14 and 14' in the wall of this bore which permit the locking disk 17 to be turned to a certain extent relative to the longitudinal projections 4 on rocking members 2 and 2'. After the rockingmember 2 has been inserted into the bores in the chain links and in locking disk 17 into a position in which the longitudinal projection 4 on this rocking memher 2 engages into the recesses 5 in one side of the bore of the chain links, the locking disk 17 is turned so that its locking portion 12 is fully inserted into the locking groove 13 in rocking member 2, whereupon the other rocking member 2 may also be inserted. Both rocking members 2 and 2 may then be locked by turning the locking disk 17 back to an intermediate position in which the locking portion 12 engages into the locking grooves 13 of both rocking members. This locking disk 17 is likewise provided with a projecting lug 9 which, when the disk is in its final locking position, is bent over the adjacent chain link so that the disk can thereafter no longer be turned.

FIGURES 8 and 9 illustrate a further modification of the invention in which the longitudinal projection 4 on each rocking member 2 and 2 is provided near its outer ends with a pair of locking grooves 3 and 3. A pair .of slotted resilient locking rings 15 which have an inner diameter slightly larger than the outer diameter of the pair of rocking members 2 and 2' may be snapped over both rocking members and into the locking grooves 3 and 3 thereof.

FIGURE 11 illustrates a locking device similar to that according to FIGURES 8 and 9, in which, however, the locking ring 16 is made more resilient by being bent so as to have a U-shaped projection 19 opposite to the slot 18. If the slot 18 is made of a slightly greater width, it is also possible to fit the locking ring 16 transversely over both rocking members 2 and 2 simultaneously after they have been fully inserted into the chain links 1 and 1.

Instead of employing a spring ring as shown in FIG- URES 8 and 11, it is also possible, as illustrated in FIG- URE 10, to fit a U-shaped wire 20 of a soft material over the two rocking members 2 and 2' and into the locking grooves 3 thereof after both rocking members have been inserted, and then to bend the ends of this wire 2d toward each other over the rocking members.

FIGURE 12 finally illustrates a locking device similar to that as shown in FIGURE 11, in which a resilient locking ring 21 is designed so as to engage into locking grooves 13 in one longitudinal edge of each rocking member 2 and 2' similarly as shown in FIGURE 6.

The locking devices as previously described and illustrated in FIGURES l to 12 may be employed either for one-piece chain links or for chain links which are composed of a plurality of individual side bars. FIGURES 13 to 16 illustrate a locking device according to a further modification of the invention which, however, may be employed only in a side-bar chain. It comprises a looking element 22 which has a shape similar to a side bar of a chain link and is provided with detents 23 and 23 which project toward the inside of the bores through which the two pairs of rocking members 24 and 24' are inserted. Each of these bores of the element 22 is ovally enlarged in the direction transverse to the direction of travel of the chain for a distance equal to the height of the detents 23 and 23' so as to permit the rocking members 24 and 24' to be inserted above the detents 23 and 23'. Each of these rocking members is provided centrally within its outer longitudinal side with a continuous V- shaped notch 25. After the rocking members 24 and 24' have been inserted into the bores in the side bars of the chain links and into the upper part of the bores in the locking element 22, the locking element may be pulled upwardly whereby the two outer rocking members 24 which are associated with the same chain link are locked against sliding transversely to the direction of the chain by the engagement of the detents Z3 and 23 into the locking grooves 13 in the lower edge of these rocking members 24'. Each of the other rocking members 24 of the two pairs is locked by another locking element 22 which is associated with the adjacent chain link at the right or left of the link under discussion and is laterally spaced from the first locking element 22 so that, when these locking elements are drawn upwardly, their detents 23 or 23' enter into the other locking groove 13 of the rocking members 24. In order to simplify the manufacture of the rocking members, each of them is provided with two transverse locking grooves 13, although only one or the other of these grooves is required for locking the respective rocking member. As indicated more clearly in FIGURE 16 which shows a top View of the part of the chain as illustrated in FIGURE 14, a U-shaped bracket 26 the central part of which is broken away in FIGURE 16 is slipped from above over the entire set of side bars for the purpose of holding the set together. FIGURE 16 also clearly shows the lug 9 on each locking element 22 which, after this locking element has been pulled upwardly and fitted into the locking grooves 13 of rocking members 24 and 24, is bent over the adjacent side bar 31 or 31 of the chain link and thereby maintains the locking element 22 in its locking position. Of course, a locking element similar to that as shown in FIGURE 13 may also be employed in combination with rocking members 2 and 2 similar to those as shown in FIGURE 6 which are provided on their outer sides with longitudinal projections 4 which engage into recesses in the side bars 31 and 31'. In such a case, the locking element 22 must also be provided with lateral recesses similar to the recesses 14 and 14 as shown in FIGURE 5 to permit the locking element to be pivoted during the assembly of the chain.

FIGURES 17 to 20 illustrate a further modification of the invention, in which each pair of adjacent chain links is composed of parallel side bars 31 and 31', as shown particularly in FIGURE 20, which are pivotably connected to each other by a pair of rocking members 24 and 24' and are held together by U-shaped brackets 26. One side bar of each chain link difiers from the other side bars so as also to serve as a locking element for preventing the rocking members which are associated with this link from sliding longitudinally. One of these locking bars 27 is illustrated particularly in FIGURES l7 and 18. Whereas each bore of the normal side bars of each link is provided with a detent which is adapted to engage into the longitudinal groove 25 in the rocking member 24 or 24 which is associated with the particular link so as to prevent this rocking member from turning relative to this link, these detents are omitted in the bores of the locking bars 27. However, adjacent to one of the longitudinal sides of this locking bar 27, each bore thereof is provided with a locking detent 28 or 28 which is adapted to engage into one of the locking grooves 13 of the associated rocking member 24 or 24. When the chain is being assembled, one of the rocking members 24 is inserted, for example, into the left bore of the chain link as shown in FIGURE 18. The insertion of this rocking member 24 requires, however, this member to be suitably turned and manipulated so as to evade the detents 28 and 28 of the locking bars 27. When this rocking member 24 has been properly inserted so as to be in the position as shown in FIGURE 18, the detents on the normal side bars 31 and 31 are in engagement with the longitudinal groove 25 in the rocking member 24 and the detent 28 of the locking bar 27 which forms a part of the left link of the three links as shown in FIG- URE 18 engages into one of the locking grooves 13 of the rocking member 24'. Thereafter, the central locking bar 27, as shown in FIGURE 18, is pivoted downwardly about the rocking member 24 until the detent 28 no longer interferes with the insertion of the other rocking member 24' into the same bore since the detent 28 is then located within the upper sector-shaped gap between the two rocking members 24 and 24'. Since the locking bars 27 dilfer from the normal side bars by not being provided with any detents which have to engage into the longitudinal grooves 25 of the rocking members, the rocking member 24 may be easily inserted after the central locking bar 27 has been pivoted downwardly. After this rocking member 24' has also been properly inserted, the locking bar 27 is pivoted back to its normal position as shown in FIGURE 18 so that both rocking members 24 and 24' are then locked against sliding in their longitudinal direction. The detents 28 of the locking bar 27 at the left of the central bar 27 according to FIGURE 18 then lock the rocking members 24, while the detents 28' of the central locking bar 27 lock the rocking members 24'. Of course, it is easily possible also to employ the locking bars 27 for rocking members 2 and 2 of a type as previously described which are provided with longitudinal projections 4, although the walls of the bores in each locking bar must then also be provided with lateral recesses similarly as shown in FIGURE 5 for receiving the projections 4 and for permitting the locking bars to be pivoted during the assembly of the chain.

If the chain according to the invention is of an endless type, it is necessary to provide a different locking device for locking the rocking pins of the chain link Which is the last to be assembled, for example, a device as shown in FIGURES 2, 5, or 8, and to omit the detent 28' of the last bar 27.

Although our invention has been illustrated and described with reference to the preferred embodiments thereof, we wish to have it understood that it is in no way limited to the details of such embodiments but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed our invention, what we claim is:

1. A link chain comprising a plurality of chain links each having transverse bores in both ends thereof, a link pin means in each of said bores for pivotably connecting the adjacent links to each other, each of said link pin means consisting of a pair of rocking members, each of said rocking members of one pair being associated with and nonrotatable relative to one of two adjacent links, and each of said rocking members having two opposite sides, one of said sides being curved and facing the other rocking member of said pair and adapted to rock thereon when the adjacent links are pivoted relative to each other, and the other side facing the wall of said bore, locking means on each rocking member and on the associated link for preventing said rocking member from turning relative to said associated link, each of said rocking members having at least one locking groove extending transversely to its longitudinal direction but only within a part of its peripheral surface, and a locking element inserted into said locking groove for preventing said rocking member from sliding longitudinally within said bore.

2. A link chain as defined in claim 1, in which each of said rocking members has a pair of longitudinal edges connecting said opposite sides, said locking groove being provided in at least one of said edges.

3. A link chain as defined in claim 2, in which said locking element consists of a substantially circular locking disk having a bore of a diameter slightly larger than that of said bore in each chain link, the wall of said bore in said locking disk having an inwardly projecting locking portion adapted to engage into said locking groove in at least one of said rocking members, said locking disk having an outwardly projecting lug adapted to be bent over the adjacent link so as to maintain said disk in its locking position after a pair of said rocking members has been inserted into said bores of said adjacent links and of said locking disk and after said disk has been turned about said rocking members until said locking portion engages into said locking groove of at least one of said rocking members and said lug then projects from said chain links.

4. A link chain as defined in claim 2, in which said locking element consists of a slotted spring ring which in its contracted position has an inner diameter slightly larger than the outer diameter of a pair of said rocking members, the side of said spring ring opposite to the slot between its ends being bent inwardly and adapted to engage into said locking groove in one longitudinal edge of each rocking member of said pair.

5. A link chain as defined in claim 2, in which each of said chain links consists of a plurality of parallel side bars and means for clamping said side bars together so as to form a set, said locking element consisting of a locking plate having two bores and a shape similar to one of said side bars and being adapted to be inserted between the side bars of one of said links, the wall of each of said bores of said locking plate having an inwardly projecting detent near one longitudinal side of said plate, said detent being adapted to be inserted into said locking groove of that rocking member of each pair which is directly associated with the chain link into which said locking plate is inserted, said bores in said locking plate being elongated in a direction transverse to its longitudinal sides for a distance at least equal to the maximum height of said detent from the wall of said bore, said rocking members being adapted to be inserted into the bores of said side bars and of said locking plate, while said locking plate is olfset relative to said side bars so that said rocking members may then be inserted above said detents into said bores of said locking plate, and an outwardly projecting lug on the other longitudinal side of said locking plate, said lug being adapted to be bent over the adjacent side bar of said link so as to mantain said locking plate in its locking position after said plate has been shifted to a position in which said detents engage into said locking grooves of the two rocking members which are associated with said chain link and each of which is inserted in a difierent bore of said link.

6. A link chain as defined in claim 2, in which each of said chain links consists of a plurality of parallel side bars each having two bores and means for clamping said side bars together so as to form a set, one of said side bars forming said locking element, the wall of each of said bores in said locking bar having an inwardly projecting detent near one longitudinal side of said bar, said detent being adapted to be inserted into said locking groove in that rocking member of each pair which is directly associated with the chain link containing said locking bar, said locking means for preventing one of said rocking members from turning relative to said associated link comprising interengaging projections and recesses on said rocking member and all of said side bars of said chain link except on said locking bar, so that during the insertion of said rocking members into said bores of a chain link the locking bar of said link may be pivoted relative to the other side bars of said link so as to permit said rocking members also to be inserted into the bores of said locking bar.

7. A link chain as defined in claim 1, in which said locking means comprise a substantially central projection on said other side of each rocking member and extending substantially along the length thereof, and a recess in the wall of said bore adapted to receive said projection, said locking groove extending transversely through said projection.

8. A link chain as defined in claim 7, in which said locking element consists of a thin substantially circular locking disk having a bore of a diameter slightly larger than that of said bore in each chain link, the wall of said bore in said locking disk having a recess permitting said projection of one of said rocking members to be passed therethrough, said locking disk having an outwardly projecting lug adapted to be bent over the adjacent link so as to maintain said disk in its locking position after a pair of said rocking members has been inserted into said bores of said adjacent links and of said locking disk and after said locking disk has been inserted into said locking grooves of said rocking members by being turned about lsaid members until said lug projects from said adjacent inks.

9. A link chain as defined in claim 8, in which said locking disk has an opening in the side thereof opposite to said lug so that the remainder forms a bifurcated mem- 11 her which is adapted to be slipped over said pair of rocking members in a direction at right angles thereto and into said locking grooves thereof after said rocking members have been installed in the bore of said adjacent links.

10. A link chain as defined in claim 7, in which said locking element consists of a substantially U-shaped wire of a soft material which, after said pair of rocking members is installed in said bore of said adjacent links, may be slipped over said pair and into said locking grooves thereof, whereupon the free ends of said wire may be bent toward each other over said rocking members.

11'. A link chain as defined in claim 1, in which said locking element consists of a slotted spring ring which in its contracted position has an inner diameter slightly larger than the outer diameter of a pair of said rocking members.

12 12. A link chain as defined in claim 11, in which said spring ring has an outwardly bent U-shaped part at the side thereof opposite to the slot between its ends.

References Cited UNITED STATES PATENTS 979,151 12/1910 Gits 74-236 1,691,871 11/1928 Reeves 74235 X 1,755,887 4/1930 Morse 74-253 2,913,916 11/1959 Schmidt 74-230.17 3,043,154 7/1962 Karig et a1. 74-253 3,071,020 1/1963 Maurer et al. 74236 3,089,346 5/1963 Dittrich 74-236 FRED C. MATTERN, JR., Primary Examiner.

I. A. WONG, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,353,421 November 21, 1967 Walter Ketterle et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the heading to the printed specification, lines 5 and 6, for "assignors to Reimers Getriebe Kommanditgesellschaft, Ascona, Switzerland" read assignors, by mesne assignments, to Reimers Getriebe AG, Zug, Switzerland, a firm of Switzerland Signed and sealed this 4th day of March 1969.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer 

1. A LINK CHAIN COMPRISING A PLURALITY OF CHAIN LINKS EACH HAVING TRANSVERSE BORES IN BOTH END THEREOF, A LINK PIN MEANS IN EACH OF SAID BORES FOR PIVOTABLY CONNECTING THE ADJACENT LINKS TO EACH OTHER, EACH OF SAID LINK PIN MEANS CONSISTING OF A PAIR OF ROCKING MEMBERS, EACH OF SAID ROCKING MEMBERS OF ONE PAIR BEING ASSOCIATED WITH AND NONROTATABLE RELATIVE TO ONE OF TWO ADJACENT LINKS, AND EACH OF SAID ROCKING MEMBERS HAVING TWO OPPOSITE SIDES, ONE OF SAID SIDES BEING CURVED AND FACING THE OTHER ROCKING MEMBER OF SAID PAIR AND ADAPTED TO ROCK THEREON WHEN THE ADJACENT LINKS ARE PIVOTED RELATIVE TO EACH OTHER, AND THE OTHER SIDE FACING THE WALL OF SAID BORE, LOCKING MEANS ON EACH ROCKING MEMBER AND ON THE ASSOCIATED LINK FOR PREVENTING SAID ROCKING MEMBER FROM TURNING RELATIVE TO SAID ASSOCIATED LINK, EACH OF SAID ROCKING MEMBERS HAVING AT LEAST ONE LOCKING GROOVE EXTENDING TRANSVERSELY TO ITS LONGITUDINAL DIRECTION BUT ONLY WITHIN A PART OF ITS PERIPHERAL SURFACE, AND A LOCKING ELEMENT INSERTED INTO SAID LOCKING GROOVE FOR PREVENTING SAID ROCKING MEMBER FROM SLIDING LONGITUDINALLY WITHIN SAID BORE. 